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[PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()

Barry Song posted 6 patches 1 year, 7 months ago
There is a newer version of this series
[PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()
Posted by Barry Song 1 year, 7 months ago 
From: Barry Song <v-songbaohua@oppo.com>

To streamline maintenance efforts, we propose discontinuing the use of
swap_free(). Instead, we can simply invoke swap_free_nr() with nr set
to 1. This adjustment offers the advantage of enabling batch processing
within kernel/power/swap.c. Furthermore, swap_free_nr() is designed with
a bitmap consisting of only one long, resulting in overhead that can be
ignored for cases where nr equals 1.

Suggested-by: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Hugh Dickins <hughd@google.com>
---
 include/linux/swap.h |  5 -----
 kernel/power/swap.c  |  7 +++----
 mm/memory.c          |  2 +-
 mm/rmap.c            |  4 ++--
 mm/shmem.c           |  4 ++--
 mm/swapfile.c        | 19 +++++--------------
 6 files changed, 13 insertions(+), 28 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index d1d35e92d7e9..f03cb446124e 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -482,7 +482,6 @@ extern int add_swap_count_continuation(swp_entry_t, gfp_t);
 extern void swap_shmem_alloc(swp_entry_t);
 extern int swap_duplicate(swp_entry_t);
 extern int swapcache_prepare(swp_entry_t);
-extern void swap_free(swp_entry_t);
 extern void swap_free_nr(swp_entry_t entry, int nr_pages);
 extern void swapcache_free_entries(swp_entry_t *entries, int n);
 extern void free_swap_and_cache_nr(swp_entry_t entry, int nr);
@@ -561,10 +560,6 @@ static inline int swapcache_prepare(swp_entry_t swp)
 	return 0;
 }
 
-static inline void swap_free(swp_entry_t swp)
-{
-}
-
 static inline void swap_free_nr(swp_entry_t entry, int nr_pages)
 {
 }
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 5bc04bfe2db1..6befaa88a342 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -181,7 +181,7 @@ sector_t alloc_swapdev_block(int swap)
 	offset = swp_offset(get_swap_page_of_type(swap));
 	if (offset) {
 		if (swsusp_extents_insert(offset))
-			swap_free(swp_entry(swap, offset));
+			swap_free_nr(swp_entry(swap, offset), 1);
 		else
 			return swapdev_block(swap, offset);
 	}
@@ -200,12 +200,11 @@ void free_all_swap_pages(int swap)
 
 	while ((node = swsusp_extents.rb_node)) {
 		struct swsusp_extent *ext;
-		unsigned long offset;
 
 		ext = rb_entry(node, struct swsusp_extent, node);
 		rb_erase(node, &swsusp_extents);
-		for (offset = ext->start; offset <= ext->end; offset++)
-			swap_free(swp_entry(swap, offset));
+		swap_free_nr(swp_entry(swap, ext->start),
+			     ext->end - ext->start + 1);
 
 		kfree(ext);
 	}
diff --git a/mm/memory.c b/mm/memory.c
index eea6e4984eae..f033eb3528ba 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4225,7 +4225,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
 	 * We're already holding a reference on the page but haven't mapped it
 	 * yet.
 	 */
-	swap_free(entry);
+	swap_free_nr(entry, 1);
 	if (should_try_to_free_swap(folio, vma, vmf->flags))
 		folio_free_swap(folio);
 
diff --git a/mm/rmap.c b/mm/rmap.c
index 087a79f1f611..39ec7742acec 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1865,7 +1865,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
 				goto walk_done_err;
 			}
 			if (arch_unmap_one(mm, vma, address, pteval) < 0) {
-				swap_free(entry);
+				swap_free_nr(entry, 1);
 				set_pte_at(mm, address, pvmw.pte, pteval);
 				goto walk_done_err;
 			}
@@ -1873,7 +1873,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
 			/* See folio_try_share_anon_rmap(): clear PTE first. */
 			if (anon_exclusive &&
 			    folio_try_share_anon_rmap_pte(folio, subpage)) {
-				swap_free(entry);
+				swap_free_nr(entry, 1);
 				set_pte_at(mm, address, pvmw.pte, pteval);
 				goto walk_done_err;
 			}
diff --git a/mm/shmem.c b/mm/shmem.c
index fa2a0ed97507..bfc8a2beb24f 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1836,7 +1836,7 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
 	 * in shmem_evict_inode().
 	 */
 	shmem_recalc_inode(inode, -1, -1);
-	swap_free(swap);
+	swap_free_nr(swap, 1);
 }
 
 /*
@@ -1927,7 +1927,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
 
 	delete_from_swap_cache(folio);
 	folio_mark_dirty(folio);
-	swap_free(swap);
+	swap_free_nr(swap, 1);
 	put_swap_device(si);
 
 	*foliop = folio;
diff --git a/mm/swapfile.c b/mm/swapfile.c
index ec12f2b9d229..ddcd0f24b9a1 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1343,19 +1343,6 @@ static void swap_entry_free(struct swap_info_struct *p, swp_entry_t entry)
 	swap_range_free(p, offset, 1);
 }
 
-/*
- * Caller has made sure that the swap device corresponding to entry
- * is still around or has not been recycled.
- */
-void swap_free(swp_entry_t entry)
-{
-	struct swap_info_struct *p;
-
-	p = _swap_info_get(entry);
-	if (p)
-		__swap_entry_free(p, entry);
-}
-
 static void cluster_swap_free_nr(struct swap_info_struct *sis,
 		unsigned long offset, int nr_pages)
 {
@@ -1385,6 +1372,10 @@ static void cluster_swap_free_nr(struct swap_info_struct *sis,
 	unlock_cluster_or_swap_info(sis, ci);
 }
 
+/*
+ * Caller has made sure that the swap device corresponding to entry
+ * is still around or has not been recycled.
+ */
 void swap_free_nr(swp_entry_t entry, int nr_pages)
 {
 	int nr;
@@ -1930,7 +1921,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
 		new_pte = pte_mkuffd_wp(new_pte);
 setpte:
 	set_pte_at(vma->vm_mm, addr, pte, new_pte);
-	swap_free(entry);
+	swap_free_nr(entry, 1);
 out:
 	if (pte)
 		pte_unmap_unlock(pte, ptl);
-- 
2.34.1
Re: [PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()
Posted by Ryan Roberts 1 year, 7 months ago 
On 03/05/2024 01:50, Barry Song wrote:
> From: Barry Song <v-songbaohua@oppo.com>
> 
> To streamline maintenance efforts, we propose discontinuing the use of
> swap_free(). Instead, we can simply invoke swap_free_nr() with nr set
> to 1. This adjustment offers the advantage of enabling batch processing
> within kernel/power/swap.c. Furthermore, swap_free_nr() is designed with
> a bitmap consisting of only one long, resulting in overhead that can be
> ignored for cases where nr equals 1.
> 
> Suggested-by: "Huang, Ying" <ying.huang@intel.com>
> Signed-off-by: Barry Song <v-songbaohua@oppo.com>
> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> Cc: Pavel Machek <pavel@ucw.cz>
> Cc: Len Brown <len.brown@intel.com>
> Cc: Hugh Dickins <hughd@google.com>
> ---
>  include/linux/swap.h |  5 -----
>  kernel/power/swap.c  |  7 +++----
>  mm/memory.c          |  2 +-
>  mm/rmap.c            |  4 ++--
>  mm/shmem.c           |  4 ++--
>  mm/swapfile.c        | 19 +++++--------------
>  6 files changed, 13 insertions(+), 28 deletions(-)
> 
> diff --git a/include/linux/swap.h b/include/linux/swap.h
> index d1d35e92d7e9..f03cb446124e 100644
> --- a/include/linux/swap.h
> +++ b/include/linux/swap.h
> @@ -482,7 +482,6 @@ extern int add_swap_count_continuation(swp_entry_t, gfp_t);
>  extern void swap_shmem_alloc(swp_entry_t);
>  extern int swap_duplicate(swp_entry_t);
>  extern int swapcache_prepare(swp_entry_t);
> -extern void swap_free(swp_entry_t);

I wonder if it would be cleaner to:

#define swap_free(entry) swap_free_nr((entry), 1)

To save all the churn for the callsites that just want to pass a single entry?

>  extern void swap_free_nr(swp_entry_t entry, int nr_pages);
>  extern void swapcache_free_entries(swp_entry_t *entries, int n);
>  extern void free_swap_and_cache_nr(swp_entry_t entry, int nr);
> @@ -561,10 +560,6 @@ static inline int swapcache_prepare(swp_entry_t swp)
>  	return 0;
>  }
>  
> -static inline void swap_free(swp_entry_t swp)
> -{
> -}
> -
>  static inline void swap_free_nr(swp_entry_t entry, int nr_pages)
>  {
>  }
> diff --git a/kernel/power/swap.c b/kernel/power/swap.c
> index 5bc04bfe2db1..6befaa88a342 100644
> --- a/kernel/power/swap.c
> +++ b/kernel/power/swap.c
> @@ -181,7 +181,7 @@ sector_t alloc_swapdev_block(int swap)
>  	offset = swp_offset(get_swap_page_of_type(swap));
>  	if (offset) {
>  		if (swsusp_extents_insert(offset))
> -			swap_free(swp_entry(swap, offset));
> +			swap_free_nr(swp_entry(swap, offset), 1);
>  		else
>  			return swapdev_block(swap, offset);
>  	}
> @@ -200,12 +200,11 @@ void free_all_swap_pages(int swap)
>  
>  	while ((node = swsusp_extents.rb_node)) {
>  		struct swsusp_extent *ext;
> -		unsigned long offset;
>  
>  		ext = rb_entry(node, struct swsusp_extent, node);
>  		rb_erase(node, &swsusp_extents);
> -		for (offset = ext->start; offset <= ext->end; offset++)
> -			swap_free(swp_entry(swap, offset));
> +		swap_free_nr(swp_entry(swap, ext->start),
> +			     ext->end - ext->start + 1);
>  
>  		kfree(ext);
>  	}
> diff --git a/mm/memory.c b/mm/memory.c
> index eea6e4984eae..f033eb3528ba 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -4225,7 +4225,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
>  	 * We're already holding a reference on the page but haven't mapped it
>  	 * yet.
>  	 */
> -	swap_free(entry);
> +	swap_free_nr(entry, 1);
>  	if (should_try_to_free_swap(folio, vma, vmf->flags))
>  		folio_free_swap(folio);
>  
> diff --git a/mm/rmap.c b/mm/rmap.c
> index 087a79f1f611..39ec7742acec 100644
> --- a/mm/rmap.c
> +++ b/mm/rmap.c
> @@ -1865,7 +1865,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
>  				goto walk_done_err;
>  			}
>  			if (arch_unmap_one(mm, vma, address, pteval) < 0) {
> -				swap_free(entry);
> +				swap_free_nr(entry, 1);
>  				set_pte_at(mm, address, pvmw.pte, pteval);
>  				goto walk_done_err;
>  			}
> @@ -1873,7 +1873,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
>  			/* See folio_try_share_anon_rmap(): clear PTE first. */
>  			if (anon_exclusive &&
>  			    folio_try_share_anon_rmap_pte(folio, subpage)) {
> -				swap_free(entry);
> +				swap_free_nr(entry, 1);
>  				set_pte_at(mm, address, pvmw.pte, pteval);
>  				goto walk_done_err;
>  			}
> diff --git a/mm/shmem.c b/mm/shmem.c
> index fa2a0ed97507..bfc8a2beb24f 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -1836,7 +1836,7 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
>  	 * in shmem_evict_inode().
>  	 */
>  	shmem_recalc_inode(inode, -1, -1);
> -	swap_free(swap);
> +	swap_free_nr(swap, 1);
>  }
>  
>  /*
> @@ -1927,7 +1927,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
>  
>  	delete_from_swap_cache(folio);
>  	folio_mark_dirty(folio);
> -	swap_free(swap);
> +	swap_free_nr(swap, 1);
>  	put_swap_device(si);
>  
>  	*foliop = folio;
> diff --git a/mm/swapfile.c b/mm/swapfile.c
> index ec12f2b9d229..ddcd0f24b9a1 100644
> --- a/mm/swapfile.c
> +++ b/mm/swapfile.c
> @@ -1343,19 +1343,6 @@ static void swap_entry_free(struct swap_info_struct *p, swp_entry_t entry)
>  	swap_range_free(p, offset, 1);
>  }
>  
> -/*
> - * Caller has made sure that the swap device corresponding to entry
> - * is still around or has not been recycled.
> - */
> -void swap_free(swp_entry_t entry)
> -{
> -	struct swap_info_struct *p;
> -
> -	p = _swap_info_get(entry);
> -	if (p)
> -		__swap_entry_free(p, entry);
> -}
> -
>  static void cluster_swap_free_nr(struct swap_info_struct *sis,
>  		unsigned long offset, int nr_pages)
>  {
> @@ -1385,6 +1372,10 @@ static void cluster_swap_free_nr(struct swap_info_struct *sis,
>  	unlock_cluster_or_swap_info(sis, ci);
>  }
>  
> +/*
> + * Caller has made sure that the swap device corresponding to entry
> + * is still around or has not been recycled.
> + */
>  void swap_free_nr(swp_entry_t entry, int nr_pages)
>  {
>  	int nr;
> @@ -1930,7 +1921,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
>  		new_pte = pte_mkuffd_wp(new_pte);
>  setpte:
>  	set_pte_at(vma->vm_mm, addr, pte, new_pte);
> -	swap_free(entry);
> +	swap_free_nr(entry, 1);
>  out:
>  	if (pte)
>  		pte_unmap_unlock(pte, ptl);
Re: [PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()
Posted by Huang, Ying 1 year, 7 months ago 
Ryan Roberts <ryan.roberts@arm.com> writes:

> On 03/05/2024 01:50, Barry Song wrote:
>> From: Barry Song <v-songbaohua@oppo.com>
>> 
>> To streamline maintenance efforts, we propose discontinuing the use of
>> swap_free(). Instead, we can simply invoke swap_free_nr() with nr set
>> to 1. This adjustment offers the advantage of enabling batch processing
>> within kernel/power/swap.c. Furthermore, swap_free_nr() is designed with
>> a bitmap consisting of only one long, resulting in overhead that can be
>> ignored for cases where nr equals 1.
>> 
>> Suggested-by: "Huang, Ying" <ying.huang@intel.com>
>> Signed-off-by: Barry Song <v-songbaohua@oppo.com>
>> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
>> Cc: Pavel Machek <pavel@ucw.cz>
>> Cc: Len Brown <len.brown@intel.com>
>> Cc: Hugh Dickins <hughd@google.com>
>> ---
>>  include/linux/swap.h |  5 -----
>>  kernel/power/swap.c  |  7 +++----
>>  mm/memory.c          |  2 +-
>>  mm/rmap.c            |  4 ++--
>>  mm/shmem.c           |  4 ++--
>>  mm/swapfile.c        | 19 +++++--------------
>>  6 files changed, 13 insertions(+), 28 deletions(-)
>> 
>> diff --git a/include/linux/swap.h b/include/linux/swap.h
>> index d1d35e92d7e9..f03cb446124e 100644
>> --- a/include/linux/swap.h
>> +++ b/include/linux/swap.h
>> @@ -482,7 +482,6 @@ extern int add_swap_count_continuation(swp_entry_t, gfp_t);
>>  extern void swap_shmem_alloc(swp_entry_t);
>>  extern int swap_duplicate(swp_entry_t);
>>  extern int swapcache_prepare(swp_entry_t);
>> -extern void swap_free(swp_entry_t);
>
> I wonder if it would be cleaner to:
>
> #define swap_free(entry) swap_free_nr((entry), 1)
>
> To save all the churn for the callsites that just want to pass a single entry?

I prefer this way.  Although I prefer inline functions.

Otherwise, LGTM.  Feel free to add

Reviewed-by: "Huang, Ying" <ying.huang@intel.com>

in the future version.

>>  extern void swap_free_nr(swp_entry_t entry, int nr_pages);
>>  extern void swapcache_free_entries(swp_entry_t *entries, int n);
>>  extern void free_swap_and_cache_nr(swp_entry_t entry, int nr);
>> @@ -561,10 +560,6 @@ static inline int swapcache_prepare(swp_entry_t swp)
>>  	return 0;
>>  }
>>  
>> -static inline void swap_free(swp_entry_t swp)
>> -{
>> -}
>> -
>>  static inline void swap_free_nr(swp_entry_t entry, int nr_pages)
>>  {
>>  }
>> diff --git a/kernel/power/swap.c b/kernel/power/swap.c
>> index 5bc04bfe2db1..6befaa88a342 100644
>> --- a/kernel/power/swap.c
>> +++ b/kernel/power/swap.c
>> @@ -181,7 +181,7 @@ sector_t alloc_swapdev_block(int swap)
>>  	offset = swp_offset(get_swap_page_of_type(swap));
>>  	if (offset) {
>>  		if (swsusp_extents_insert(offset))
>> -			swap_free(swp_entry(swap, offset));
>> +			swap_free_nr(swp_entry(swap, offset), 1);
>>  		else
>>  			return swapdev_block(swap, offset);
>>  	}
>> @@ -200,12 +200,11 @@ void free_all_swap_pages(int swap)
>>  
>>  	while ((node = swsusp_extents.rb_node)) {
>>  		struct swsusp_extent *ext;
>> -		unsigned long offset;
>>  
>>  		ext = rb_entry(node, struct swsusp_extent, node);
>>  		rb_erase(node, &swsusp_extents);
>> -		for (offset = ext->start; offset <= ext->end; offset++)
>> -			swap_free(swp_entry(swap, offset));
>> +		swap_free_nr(swp_entry(swap, ext->start),
>> +			     ext->end - ext->start + 1);
>>  
>>  		kfree(ext);
>>  	}
>> diff --git a/mm/memory.c b/mm/memory.c
>> index eea6e4984eae..f033eb3528ba 100644
>> --- a/mm/memory.c
>> +++ b/mm/memory.c
>> @@ -4225,7 +4225,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
>>  	 * We're already holding a reference on the page but haven't mapped it
>>  	 * yet.
>>  	 */
>> -	swap_free(entry);
>> +	swap_free_nr(entry, 1);
>>  	if (should_try_to_free_swap(folio, vma, vmf->flags))
>>  		folio_free_swap(folio);
>>  
>> diff --git a/mm/rmap.c b/mm/rmap.c
>> index 087a79f1f611..39ec7742acec 100644
>> --- a/mm/rmap.c
>> +++ b/mm/rmap.c
>> @@ -1865,7 +1865,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
>>  				goto walk_done_err;
>>  			}
>>  			if (arch_unmap_one(mm, vma, address, pteval) < 0) {
>> -				swap_free(entry);
>> +				swap_free_nr(entry, 1);
>>  				set_pte_at(mm, address, pvmw.pte, pteval);
>>  				goto walk_done_err;
>>  			}
>> @@ -1873,7 +1873,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
>>  			/* See folio_try_share_anon_rmap(): clear PTE first. */
>>  			if (anon_exclusive &&
>>  			    folio_try_share_anon_rmap_pte(folio, subpage)) {
>> -				swap_free(entry);
>> +				swap_free_nr(entry, 1);
>>  				set_pte_at(mm, address, pvmw.pte, pteval);
>>  				goto walk_done_err;
>>  			}
>> diff --git a/mm/shmem.c b/mm/shmem.c
>> index fa2a0ed97507..bfc8a2beb24f 100644
>> --- a/mm/shmem.c
>> +++ b/mm/shmem.c
>> @@ -1836,7 +1836,7 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
>>  	 * in shmem_evict_inode().
>>  	 */
>>  	shmem_recalc_inode(inode, -1, -1);
>> -	swap_free(swap);
>> +	swap_free_nr(swap, 1);
>>  }
>>  
>>  /*
>> @@ -1927,7 +1927,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
>>  
>>  	delete_from_swap_cache(folio);
>>  	folio_mark_dirty(folio);
>> -	swap_free(swap);
>> +	swap_free_nr(swap, 1);
>>  	put_swap_device(si);
>>  
>>  	*foliop = folio;
>> diff --git a/mm/swapfile.c b/mm/swapfile.c
>> index ec12f2b9d229..ddcd0f24b9a1 100644
>> --- a/mm/swapfile.c
>> +++ b/mm/swapfile.c
>> @@ -1343,19 +1343,6 @@ static void swap_entry_free(struct swap_info_struct *p, swp_entry_t entry)
>>  	swap_range_free(p, offset, 1);
>>  }
>>  
>> -/*
>> - * Caller has made sure that the swap device corresponding to entry
>> - * is still around or has not been recycled.
>> - */
>> -void swap_free(swp_entry_t entry)
>> -{
>> -	struct swap_info_struct *p;
>> -
>> -	p = _swap_info_get(entry);
>> -	if (p)
>> -		__swap_entry_free(p, entry);
>> -}
>> -
>>  static void cluster_swap_free_nr(struct swap_info_struct *sis,
>>  		unsigned long offset, int nr_pages)
>>  {
>> @@ -1385,6 +1372,10 @@ static void cluster_swap_free_nr(struct swap_info_struct *sis,
>>  	unlock_cluster_or_swap_info(sis, ci);
>>  }
>>  
>> +/*
>> + * Caller has made sure that the swap device corresponding to entry
>> + * is still around or has not been recycled.
>> + */
>>  void swap_free_nr(swp_entry_t entry, int nr_pages)
>>  {
>>  	int nr;
>> @@ -1930,7 +1921,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
>>  		new_pte = pte_mkuffd_wp(new_pte);
>>  setpte:
>>  	set_pte_at(vma->vm_mm, addr, pte, new_pte);
>> -	swap_free(entry);
>> +	swap_free_nr(entry, 1);
>>  out:
>>  	if (pte)
>>  		pte_unmap_unlock(pte, ptl);

--
Best Regards,
Huang, Ying
Re: [PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()
Posted by Barry Song 1 year, 7 months ago 
On Wed, May 8, 2024 at 7:58 PM Huang, Ying <ying.huang@intel.com> wrote:
>
> Ryan Roberts <ryan.roberts@arm.com> writes:
>
> > On 03/05/2024 01:50, Barry Song wrote:
> >> From: Barry Song <v-songbaohua@oppo.com>
> >>
> >> To streamline maintenance efforts, we propose discontinuing the use of
> >> swap_free(). Instead, we can simply invoke swap_free_nr() with nr set
> >> to 1. This adjustment offers the advantage of enabling batch processing
> >> within kernel/power/swap.c. Furthermore, swap_free_nr() is designed with
> >> a bitmap consisting of only one long, resulting in overhead that can be
> >> ignored for cases where nr equals 1.
> >>
> >> Suggested-by: "Huang, Ying" <ying.huang@intel.com>
> >> Signed-off-by: Barry Song <v-songbaohua@oppo.com>
> >> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> >> Cc: Pavel Machek <pavel@ucw.cz>
> >> Cc: Len Brown <len.brown@intel.com>
> >> Cc: Hugh Dickins <hughd@google.com>
> >> ---
> >>  include/linux/swap.h |  5 -----
> >>  kernel/power/swap.c  |  7 +++----
> >>  mm/memory.c          |  2 +-
> >>  mm/rmap.c            |  4 ++--
> >>  mm/shmem.c           |  4 ++--
> >>  mm/swapfile.c        | 19 +++++--------------
> >>  6 files changed, 13 insertions(+), 28 deletions(-)
> >>
> >> diff --git a/include/linux/swap.h b/include/linux/swap.h
> >> index d1d35e92d7e9..f03cb446124e 100644
> >> --- a/include/linux/swap.h
> >> +++ b/include/linux/swap.h
> >> @@ -482,7 +482,6 @@ extern int add_swap_count_continuation(swp_entry_t, gfp_t);
> >>  extern void swap_shmem_alloc(swp_entry_t);
> >>  extern int swap_duplicate(swp_entry_t);
> >>  extern int swapcache_prepare(swp_entry_t);
> >> -extern void swap_free(swp_entry_t);
> >
> > I wonder if it would be cleaner to:
> >
> > #define swap_free(entry) swap_free_nr((entry), 1)
> >
> > To save all the churn for the callsites that just want to pass a single entry?
>
> I prefer this way.  Although I prefer inline functions.

Yes, using static inline is preferable. I've recently submitted
a checkpatch/codestyle for this, which can be found at:
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/commit/?h=mm-everything&id=39c58d5ed036
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/commit/?h=mm-everything&id=8379bf0b0e1f5

Using static inline aligns with the established rule.

>
> Otherwise, LGTM.  Feel free to add
>
> Reviewed-by: "Huang, Ying" <ying.huang@intel.com>

Thanks!

>
> in the future version.

I believe Christoph's vote leans towards simply removing swap_free_nr
and renaming it to swap_free, while adding a new parameter as follows.

void swap_free(swp_entry_t entry, int nr);
{
}

now I see Ryan and you prefer

static inline swap_free()
{
        swap_free_nr(...., 1)
}

Chris slightly favors discouraging the use of swap_free() without the
new parameter. Removing swap_free() can address this concern.

It seems that maintaining swap_free() and having it call swap_free_nr() with
a default value of 1 received the most support.

To align with free_swap_and_cache() and free_swap_and_cache_nr(),
I'll proceed with the "static inline" approach in the new version. Please
voice any objections you may have, Christoph, Chris.

>
> >>  extern void swap_free_nr(swp_entry_t entry, int nr_pages);
> >>  extern void swapcache_free_entries(swp_entry_t *entries, int n);
> >>  extern void free_swap_and_cache_nr(swp_entry_t entry, int nr);
> >> @@ -561,10 +560,6 @@ static inline int swapcache_prepare(swp_entry_t swp)
> >>      return 0;
> >>  }
> >>
> >> -static inline void swap_free(swp_entry_t swp)
> >> -{
> >> -}
> >> -
> >>  static inline void swap_free_nr(swp_entry_t entry, int nr_pages)
> >>  {
> >>  }
> >> diff --git a/kernel/power/swap.c b/kernel/power/swap.c
> >> index 5bc04bfe2db1..6befaa88a342 100644
> >> --- a/kernel/power/swap.c
> >> +++ b/kernel/power/swap.c
> >> @@ -181,7 +181,7 @@ sector_t alloc_swapdev_block(int swap)
> >>      offset = swp_offset(get_swap_page_of_type(swap));
> >>      if (offset) {
> >>              if (swsusp_extents_insert(offset))
> >> -                    swap_free(swp_entry(swap, offset));
> >> +                    swap_free_nr(swp_entry(swap, offset), 1);
> >>              else
> >>                      return swapdev_block(swap, offset);
> >>      }
> >> @@ -200,12 +200,11 @@ void free_all_swap_pages(int swap)
> >>
> >>      while ((node = swsusp_extents.rb_node)) {
> >>              struct swsusp_extent *ext;
> >> -            unsigned long offset;
> >>
> >>              ext = rb_entry(node, struct swsusp_extent, node);
> >>              rb_erase(node, &swsusp_extents);
> >> -            for (offset = ext->start; offset <= ext->end; offset++)
> >> -                    swap_free(swp_entry(swap, offset));
> >> +            swap_free_nr(swp_entry(swap, ext->start),
> >> +                         ext->end - ext->start + 1);
> >>
> >>              kfree(ext);
> >>      }
> >> diff --git a/mm/memory.c b/mm/memory.c
> >> index eea6e4984eae..f033eb3528ba 100644
> >> --- a/mm/memory.c
> >> +++ b/mm/memory.c
> >> @@ -4225,7 +4225,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
> >>       * We're already holding a reference on the page but haven't mapped it
> >>       * yet.
> >>       */
> >> -    swap_free(entry);
> >> +    swap_free_nr(entry, 1);
> >>      if (should_try_to_free_swap(folio, vma, vmf->flags))
> >>              folio_free_swap(folio);
> >>
> >> diff --git a/mm/rmap.c b/mm/rmap.c
> >> index 087a79f1f611..39ec7742acec 100644
> >> --- a/mm/rmap.c
> >> +++ b/mm/rmap.c
> >> @@ -1865,7 +1865,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
> >>                              goto walk_done_err;
> >>                      }
> >>                      if (arch_unmap_one(mm, vma, address, pteval) < 0) {
> >> -                            swap_free(entry);
> >> +                            swap_free_nr(entry, 1);
> >>                              set_pte_at(mm, address, pvmw.pte, pteval);
> >>                              goto walk_done_err;
> >>                      }
> >> @@ -1873,7 +1873,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
> >>                      /* See folio_try_share_anon_rmap(): clear PTE first. */
> >>                      if (anon_exclusive &&
> >>                          folio_try_share_anon_rmap_pte(folio, subpage)) {
> >> -                            swap_free(entry);
> >> +                            swap_free_nr(entry, 1);
> >>                              set_pte_at(mm, address, pvmw.pte, pteval);
> >>                              goto walk_done_err;
> >>                      }
> >> diff --git a/mm/shmem.c b/mm/shmem.c
> >> index fa2a0ed97507..bfc8a2beb24f 100644
> >> --- a/mm/shmem.c
> >> +++ b/mm/shmem.c
> >> @@ -1836,7 +1836,7 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
> >>       * in shmem_evict_inode().
> >>       */
> >>      shmem_recalc_inode(inode, -1, -1);
> >> -    swap_free(swap);
> >> +    swap_free_nr(swap, 1);
> >>  }
> >>
> >>  /*
> >> @@ -1927,7 +1927,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
> >>
> >>      delete_from_swap_cache(folio);
> >>      folio_mark_dirty(folio);
> >> -    swap_free(swap);
> >> +    swap_free_nr(swap, 1);
> >>      put_swap_device(si);
> >>
> >>      *foliop = folio;
> >> diff --git a/mm/swapfile.c b/mm/swapfile.c
> >> index ec12f2b9d229..ddcd0f24b9a1 100644
> >> --- a/mm/swapfile.c
> >> +++ b/mm/swapfile.c
> >> @@ -1343,19 +1343,6 @@ static void swap_entry_free(struct swap_info_struct *p, swp_entry_t entry)
> >>      swap_range_free(p, offset, 1);
> >>  }
> >>
> >> -/*
> >> - * Caller has made sure that the swap device corresponding to entry
> >> - * is still around or has not been recycled.
> >> - */
> >> -void swap_free(swp_entry_t entry)
> >> -{
> >> -    struct swap_info_struct *p;
> >> -
> >> -    p = _swap_info_get(entry);
> >> -    if (p)
> >> -            __swap_entry_free(p, entry);
> >> -}
> >> -
> >>  static void cluster_swap_free_nr(struct swap_info_struct *sis,
> >>              unsigned long offset, int nr_pages)
> >>  {
> >> @@ -1385,6 +1372,10 @@ static void cluster_swap_free_nr(struct swap_info_struct *sis,
> >>      unlock_cluster_or_swap_info(sis, ci);
> >>  }
> >>
> >> +/*
> >> + * Caller has made sure that the swap device corresponding to entry
> >> + * is still around or has not been recycled.
> >> + */
> >>  void swap_free_nr(swp_entry_t entry, int nr_pages)
> >>  {
> >>      int nr;
> >> @@ -1930,7 +1921,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
> >>              new_pte = pte_mkuffd_wp(new_pte);
> >>  setpte:
> >>      set_pte_at(vma->vm_mm, addr, pte, new_pte);
> >> -    swap_free(entry);
> >> +    swap_free_nr(entry, 1);
> >>  out:
> >>      if (pte)
> >>              pte_unmap_unlock(pte, ptl);
>
> --
> Best Regards,
> Huang, Ying

Thanks
Barry
Re: [PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()
Posted by Ryan Roberts 1 year, 7 months ago 
On 08/05/2024 09:30, Barry Song wrote:
> On Wed, May 8, 2024 at 7:58 PM Huang, Ying <ying.huang@intel.com> wrote:
>>
>> Ryan Roberts <ryan.roberts@arm.com> writes:
>>
>>> On 03/05/2024 01:50, Barry Song wrote:
>>>> From: Barry Song <v-songbaohua@oppo.com>
>>>>
>>>> To streamline maintenance efforts, we propose discontinuing the use of
>>>> swap_free(). Instead, we can simply invoke swap_free_nr() with nr set
>>>> to 1. This adjustment offers the advantage of enabling batch processing
>>>> within kernel/power/swap.c. Furthermore, swap_free_nr() is designed with
>>>> a bitmap consisting of only one long, resulting in overhead that can be
>>>> ignored for cases where nr equals 1.
>>>>
>>>> Suggested-by: "Huang, Ying" <ying.huang@intel.com>
>>>> Signed-off-by: Barry Song <v-songbaohua@oppo.com>
>>>> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
>>>> Cc: Pavel Machek <pavel@ucw.cz>
>>>> Cc: Len Brown <len.brown@intel.com>
>>>> Cc: Hugh Dickins <hughd@google.com>
>>>> ---
>>>>  include/linux/swap.h |  5 -----
>>>>  kernel/power/swap.c  |  7 +++----
>>>>  mm/memory.c          |  2 +-
>>>>  mm/rmap.c            |  4 ++--
>>>>  mm/shmem.c           |  4 ++--
>>>>  mm/swapfile.c        | 19 +++++--------------
>>>>  6 files changed, 13 insertions(+), 28 deletions(-)
>>>>
>>>> diff --git a/include/linux/swap.h b/include/linux/swap.h
>>>> index d1d35e92d7e9..f03cb446124e 100644
>>>> --- a/include/linux/swap.h
>>>> +++ b/include/linux/swap.h
>>>> @@ -482,7 +482,6 @@ extern int add_swap_count_continuation(swp_entry_t, gfp_t);
>>>>  extern void swap_shmem_alloc(swp_entry_t);
>>>>  extern int swap_duplicate(swp_entry_t);
>>>>  extern int swapcache_prepare(swp_entry_t);
>>>> -extern void swap_free(swp_entry_t);
>>>
>>> I wonder if it would be cleaner to:
>>>
>>> #define swap_free(entry) swap_free_nr((entry), 1)
>>>
>>> To save all the churn for the callsites that just want to pass a single entry?
>>
>> I prefer this way.  Although I prefer inline functions.

Yes, I agree inline function is the better approach.

> 
> Yes, using static inline is preferable. I've recently submitted
> a checkpatch/codestyle for this, which can be found at:
> https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/commit/?h=mm-everything&id=39c58d5ed036
> https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/commit/?h=mm-everything&id=8379bf0b0e1f5
> 
> Using static inline aligns with the established rule.
> 
>>
>> Otherwise, LGTM.  Feel free to add
>>
>> Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
> 
> Thanks!
> 
>>
>> in the future version.
> 
> I believe Christoph's vote leans towards simply removing swap_free_nr
> and renaming it to swap_free, while adding a new parameter as follows.
> 
> void swap_free(swp_entry_t entry, int nr);
> {
> }
> 
> now I see Ryan and you prefer
> 
> static inline swap_free()
> {
>         swap_free_nr(...., 1)
> }
> 
> Chris slightly favors discouraging the use of swap_free() without the
> new parameter. Removing swap_free() can address this concern.
> 
> It seems that maintaining swap_free() and having it call swap_free_nr() with
> a default value of 1 received the most support.
> 
> To align with free_swap_and_cache() and free_swap_and_cache_nr(),
> I'll proceed with the "static inline" approach in the new version. Please
> voice any objections you may have, Christoph, Chris.

I'm happy with either route. If you end up adding a nr param to swap_free() then
it would also be good to give free_swap_and_cache_nr() the same treatment.

> 
>>
>>>>  extern void swap_free_nr(swp_entry_t entry, int nr_pages);
>>>>  extern void swapcache_free_entries(swp_entry_t *entries, int n);
>>>>  extern void free_swap_and_cache_nr(swp_entry_t entry, int nr);
>>>> @@ -561,10 +560,6 @@ static inline int swapcache_prepare(swp_entry_t swp)
>>>>      return 0;
>>>>  }
>>>>
>>>> -static inline void swap_free(swp_entry_t swp)
>>>> -{
>>>> -}
>>>> -
>>>>  static inline void swap_free_nr(swp_entry_t entry, int nr_pages)
>>>>  {
>>>>  }
>>>> diff --git a/kernel/power/swap.c b/kernel/power/swap.c
>>>> index 5bc04bfe2db1..6befaa88a342 100644
>>>> --- a/kernel/power/swap.c
>>>> +++ b/kernel/power/swap.c
>>>> @@ -181,7 +181,7 @@ sector_t alloc_swapdev_block(int swap)
>>>>      offset = swp_offset(get_swap_page_of_type(swap));
>>>>      if (offset) {
>>>>              if (swsusp_extents_insert(offset))
>>>> -                    swap_free(swp_entry(swap, offset));
>>>> +                    swap_free_nr(swp_entry(swap, offset), 1);
>>>>              else
>>>>                      return swapdev_block(swap, offset);
>>>>      }
>>>> @@ -200,12 +200,11 @@ void free_all_swap_pages(int swap)
>>>>
>>>>      while ((node = swsusp_extents.rb_node)) {
>>>>              struct swsusp_extent *ext;
>>>> -            unsigned long offset;
>>>>
>>>>              ext = rb_entry(node, struct swsusp_extent, node);
>>>>              rb_erase(node, &swsusp_extents);
>>>> -            for (offset = ext->start; offset <= ext->end; offset++)
>>>> -                    swap_free(swp_entry(swap, offset));
>>>> +            swap_free_nr(swp_entry(swap, ext->start),
>>>> +                         ext->end - ext->start + 1);
>>>>
>>>>              kfree(ext);
>>>>      }
>>>> diff --git a/mm/memory.c b/mm/memory.c
>>>> index eea6e4984eae..f033eb3528ba 100644
>>>> --- a/mm/memory.c
>>>> +++ b/mm/memory.c
>>>> @@ -4225,7 +4225,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
>>>>       * We're already holding a reference on the page but haven't mapped it
>>>>       * yet.
>>>>       */
>>>> -    swap_free(entry);
>>>> +    swap_free_nr(entry, 1);
>>>>      if (should_try_to_free_swap(folio, vma, vmf->flags))
>>>>              folio_free_swap(folio);
>>>>
>>>> diff --git a/mm/rmap.c b/mm/rmap.c
>>>> index 087a79f1f611..39ec7742acec 100644
>>>> --- a/mm/rmap.c
>>>> +++ b/mm/rmap.c
>>>> @@ -1865,7 +1865,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
>>>>                              goto walk_done_err;
>>>>                      }
>>>>                      if (arch_unmap_one(mm, vma, address, pteval) < 0) {
>>>> -                            swap_free(entry);
>>>> +                            swap_free_nr(entry, 1);
>>>>                              set_pte_at(mm, address, pvmw.pte, pteval);
>>>>                              goto walk_done_err;
>>>>                      }
>>>> @@ -1873,7 +1873,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
>>>>                      /* See folio_try_share_anon_rmap(): clear PTE first. */
>>>>                      if (anon_exclusive &&
>>>>                          folio_try_share_anon_rmap_pte(folio, subpage)) {
>>>> -                            swap_free(entry);
>>>> +                            swap_free_nr(entry, 1);
>>>>                              set_pte_at(mm, address, pvmw.pte, pteval);
>>>>                              goto walk_done_err;
>>>>                      }
>>>> diff --git a/mm/shmem.c b/mm/shmem.c
>>>> index fa2a0ed97507..bfc8a2beb24f 100644
>>>> --- a/mm/shmem.c
>>>> +++ b/mm/shmem.c
>>>> @@ -1836,7 +1836,7 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
>>>>       * in shmem_evict_inode().
>>>>       */
>>>>      shmem_recalc_inode(inode, -1, -1);
>>>> -    swap_free(swap);
>>>> +    swap_free_nr(swap, 1);
>>>>  }
>>>>
>>>>  /*
>>>> @@ -1927,7 +1927,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
>>>>
>>>>      delete_from_swap_cache(folio);
>>>>      folio_mark_dirty(folio);
>>>> -    swap_free(swap);
>>>> +    swap_free_nr(swap, 1);
>>>>      put_swap_device(si);
>>>>
>>>>      *foliop = folio;
>>>> diff --git a/mm/swapfile.c b/mm/swapfile.c
>>>> index ec12f2b9d229..ddcd0f24b9a1 100644
>>>> --- a/mm/swapfile.c
>>>> +++ b/mm/swapfile.c
>>>> @@ -1343,19 +1343,6 @@ static void swap_entry_free(struct swap_info_struct *p, swp_entry_t entry)
>>>>      swap_range_free(p, offset, 1);
>>>>  }
>>>>
>>>> -/*
>>>> - * Caller has made sure that the swap device corresponding to entry
>>>> - * is still around or has not been recycled.
>>>> - */
>>>> -void swap_free(swp_entry_t entry)
>>>> -{
>>>> -    struct swap_info_struct *p;
>>>> -
>>>> -    p = _swap_info_get(entry);
>>>> -    if (p)
>>>> -            __swap_entry_free(p, entry);
>>>> -}
>>>> -
>>>>  static void cluster_swap_free_nr(struct swap_info_struct *sis,
>>>>              unsigned long offset, int nr_pages)
>>>>  {
>>>> @@ -1385,6 +1372,10 @@ static void cluster_swap_free_nr(struct swap_info_struct *sis,
>>>>      unlock_cluster_or_swap_info(sis, ci);
>>>>  }
>>>>
>>>> +/*
>>>> + * Caller has made sure that the swap device corresponding to entry
>>>> + * is still around or has not been recycled.
>>>> + */
>>>>  void swap_free_nr(swp_entry_t entry, int nr_pages)
>>>>  {
>>>>      int nr;
>>>> @@ -1930,7 +1921,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
>>>>              new_pte = pte_mkuffd_wp(new_pte);
>>>>  setpte:
>>>>      set_pte_at(vma->vm_mm, addr, pte, new_pte);
>>>> -    swap_free(entry);
>>>> +    swap_free_nr(entry, 1);
>>>>  out:
>>>>      if (pte)
>>>>              pte_unmap_unlock(pte, ptl);
>>
>> --
>> Best Regards,
>> Huang, Ying
> 
> Thanks
> Barry
Re: [PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()
Posted by Chris Li 1 year, 7 months ago 
On Fri, May 3, 2024 at 2:31 AM Ryan Roberts <ryan.roberts@arm.com> wrote:
>
> On 03/05/2024 01:50, Barry Song wrote:
> > From: Barry Song <v-songbaohua@oppo.com>
> >
> > To streamline maintenance efforts, we propose discontinuing the use of
> > swap_free(). Instead, we can simply invoke swap_free_nr() with nr set
> > to 1. This adjustment offers the advantage of enabling batch processing
> > within kernel/power/swap.c. Furthermore, swap_free_nr() is designed with
> > a bitmap consisting of only one long, resulting in overhead that can be
> > ignored for cases where nr equals 1.
> >
> > Suggested-by: "Huang, Ying" <ying.huang@intel.com>
> > Signed-off-by: Barry Song <v-songbaohua@oppo.com>
> > Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> > Cc: Pavel Machek <pavel@ucw.cz>
> > Cc: Len Brown <len.brown@intel.com>
> > Cc: Hugh Dickins <hughd@google.com>
> > ---
> >  include/linux/swap.h |  5 -----
> >  kernel/power/swap.c  |  7 +++----
> >  mm/memory.c          |  2 +-
> >  mm/rmap.c            |  4 ++--
> >  mm/shmem.c           |  4 ++--
> >  mm/swapfile.c        | 19 +++++--------------
> >  6 files changed, 13 insertions(+), 28 deletions(-)
> >
> > diff --git a/include/linux/swap.h b/include/linux/swap.h
> > index d1d35e92d7e9..f03cb446124e 100644
> > --- a/include/linux/swap.h
> > +++ b/include/linux/swap.h
> > @@ -482,7 +482,6 @@ extern int add_swap_count_continuation(swp_entry_t, gfp_t);
> >  extern void swap_shmem_alloc(swp_entry_t);
> >  extern int swap_duplicate(swp_entry_t);
> >  extern int swapcache_prepare(swp_entry_t);
> > -extern void swap_free(swp_entry_t);
>
> I wonder if it would be cleaner to:
>
> #define swap_free(entry) swap_free_nr((entry), 1)
>
> To save all the churn for the callsites that just want to pass a single entry?
>
Either way works. It will produce the same machine code. I have a
slight inclination to just drop swap_free(entry) API so that it
discourages the caller to do a for loop over swap_free().

Acked-by: Chris Li <chrisl@kernel.org>

Chris
Re: [PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()
Posted by Christoph Hellwig 1 year, 7 months ago 
On Fri, May 03, 2024 at 01:37:06PM -0700, Chris Li wrote:
> Either way works. It will produce the same machine code. I have a
> slight inclination to just drop swap_free(entry) API so that it
> discourages the caller to do a for loop over swap_free().

Then just ad the number of entries parameter to swap_free and do away
with the separate swap_free_nr.

Patchew 2.1-devel-b67e4c2

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